Order HEXANCHIFORMES
Cow & Frill sharks
The only sharks combining a single dorsal fin and 6 or 7
pairs of gill slits. Adults reach 85-482 cm total length.
Ovoviviparous. Two families of coastal and deep-water
benthic sharks distributed in all 3 major oceans.
Family No.2: HEXANCHIDAE
by A.J. Bass, P.C. Heemstra & L.J.V. Compagno
COW sharks
Koeihaaie
One dorsal fin ; anal fin present; no fin spines. Six or 7
pairs of gill slits which extend on to ventral surface of throat;
first gill slits not joined ventrally. Lateral-line canals closed.
No nictitans. Upper jaw teeth unlike lower. Claspers
sheathed by expanded inner margins of pelvic fins. Three
genera with 6 or 7 species, 4 in our area.
KEY TO GENERA
la Six gill slits ............................................... .. ......... Hexanchus
Ib Seven gill slits ............ ......................... .... .......... ..... .... .... ... 2
2a Orbit length greater than internostril distance; snout
length 1.6-2.0 times internostril distance .................. Heptranchias
2b Orbit length much less than internostril distance; snout
length 1.1-1.3 times internostril distance .................. Notorynchus
Koei- & Frilletjieshaaie
Genus Heptranchias Rafinesque, 1810
Apparently monotypic.
2.1 Heptranchias perlo
(Bonnaterre, 1788)
Sharpnose sevengill shark
Skerpneus-sewekiefhaai
Squalus perlo Bonnaterre, 1788: 668 (Mediterranean). Heptranchias
perlo: Bigelow & Schroeder, 1949: 88*; Smith, SFSA No. 33; Garrick &
Paul, 1971*; Bass et aI., 1975: 11*; Capape, 1980*; Compagno, 1981 : 2* .
Snout long and pointed; A height 0.5-0.6 x D height; spiracles minute;
precaudal vertebrae 78-90; tooth counts (of large teeth only) 9-11/9-11.
5-1-5
Ovoviviparous; litters of 9-20 pups, 25 cm at birth;
females mature at 92-100 cm, males at about 80 cm; attains
137 cm. Brownish grey, paler below, sometimes with indistinct dark blotches on body; young with D and C dark tipped, those of adults plain. Feeds on small fishes (including
sharks) and squid. Circum global in warm seas at depths of
50 - 1 000 m; in our area, specimens have been caught off
Natal, southern Mozambique and Namibia.
2.1 Heptranchias perlo: 68 em immature male (5. Mozambique). N = left nostril, d = denticles; T = teeth, upper jaw teeth (above),lower jaw teeth (below).
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Cow & Frill sharks
The only sharks combining a single dorsal fin and 6 or 7
pairs of gill slits. Adults reach 85-482 cm total length.
Ovoviviparous. Two families of coastal and deep-water
benthic sharks distributed in all 3 major oceans.
Family No.2: HEXANCHIDAE
by A.J. Bass, P.C. Heemstra & L.J.V. Compagno
COW sharks
Koeihaaie
One dorsal fin ; anal fin present; no fin spines. Six or 7
pairs of gill slits which extend on to ventral surface of throat;
first gill slits not joined ventrally. Lateral-line canals closed.
No nictitans. Upper jaw teeth unlike lower. Claspers
sheathed by expanded inner margins of pelvic fins. Three
genera with 6 or 7 species, 4 in our area.
KEY TO GENERA
la Six gill slits ............................................... .. ......... Hexanchus
Ib Seven gill slits ............ ......................... .... .......... ..... .... .... ... 2
2a Orbit length greater than internostril distance; snout
length 1.6-2.0 times internostril distance .................. Heptranchias
2b Orbit length much less than internostril distance; snout
length 1.1-1.3 times internostril distance .................. Notorynchus
Koei- & Frilletjieshaaie
Genus Heptranchias Rafinesque, 1810
Apparently monotypic.
2.1 Heptranchias perlo
(Bonnaterre, 1788)
Sharpnose sevengill shark
Skerpneus-sewekiefhaai
Squalus perlo Bonnaterre, 1788: 668 (Mediterranean). Heptranchias
perlo: Bigelow & Schroeder, 1949: 88*; Smith, SFSA No. 33; Garrick &
Paul, 1971*; Bass et aI., 1975: 11*; Capape, 1980*; Compagno, 1981 : 2* .
Snout long and pointed; A height 0.5-0.6 x D height; spiracles minute;
precaudal vertebrae 78-90; tooth counts (of large teeth only) 9-11/9-11.
5-1-5
Ovoviviparous; litters of 9-20 pups, 25 cm at birth;
females mature at 92-100 cm, males at about 80 cm; attains
137 cm. Brownish grey, paler below, sometimes with indistinct dark blotches on body; young with D and C dark tipped, those of adults plain. Feeds on small fishes (including
sharks) and squid. Circum global in warm seas at depths of
50 - 1 000 m; in our area, specimens have been caught off
Natal, southern Mozambique and Namibia.
2.1 Heptranchias perlo: 68 em immature male (5. Mozambique). N = left nostril, d = denticles; T = teeth, upper jaw teeth (above),lower jaw teeth (below).
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